1aUW10. Acoustic response of a torsional shear wave transducer in a
viscoelastic medium.

Based on a previous design of a low-frequency, torsional shear wave
transducer [A. K. Walden and T. R. Howarth, J. Acoust. Soc. Am. 91, 2463
(1992)], an analytical model is proposed to predict the radiated acoustic
field. The stress and displacement fields produced by the S-wave source are
analyzed with the appropriate boundary conditions. Then the continuity
condition of the field (elastic wave equation) is employed to investigate the
propagating subfields in the surrounding elastic/viscoelastic medium. The
transducer studied is a cylindrical-type torsional vibrator. Therefore, it
generates both horizontal and vertical radiation patterns. Computed, as well as
measured results, of the acoustic response are presented for various couplings
of different viscoelastic media with both the bimorph and torsional shear wave
transducer designs. These results are useful for an optimal shear wave
transducer design in the applications of ocean geoacoustics.